Lung Cancer

What is lung cancer?

Lung cancer is the leading cause of cancer deaths worldwide. Lung cancer is a cancer that starts in the lungs, and can spread to other areas of the body. Early symptoms of lung cancer can be subtle, but the sooner you are diagnosed, the better your treatment options and possible outcomes. Lung cancer is primarily treated with surgery, chemotherapy, and radiation. Newer treatments include immunotherapy and targeted therapy.

What are the symptoms of lung cancer?

Early symptoms of lung cancer

The early stages of lung cancer don’t always cause symptoms. When early symptoms do occur, they can include signs such as shortness of breath, along with unexpected symptoms, such as back pain. Back pain can occur when tumors cause pressure in your lungs or when they spread to your spinal cord and ribs.

Other early signs of lung cancer may include:

• A lingering or worsening cough
• Coughing up phlegm or blood
• Chest pain that worsens when you breathe deeply, laugh, or cough
• Hoarseness and wheezing
• Weakness and fatigue
• Loss of appetite and weight loss
• Recurrent respiratory infections such as pneumonia or bronchitis

Late symptoms of lung cancer

Additional symptoms of lung cancer depend on where new tumors form. Not everyone with late-stage lung cancer will experience every symptom. Late-stage symptoms might include:

• Lumps in the neck or collarbone
• Bone pain especially in the back, ribs, or hips
• Headaches
• Dizziness
• Balance issues
• Numbness in arms or legs
• Yellowing of skin and eyes (jaundice)
• Drooping of one eyelid and shrunken pupils
• Lack of perspiration on one side of the face
• Shoulder pain
• Swelling of the face and upper body

Additionally, lung cancer tumors can sometimes release a substance similar to hormones, leading to a wide variety of symptoms known as paraneoplastic syndrome. Symptoms include:

• Muscle weakness
• Nausea and vomiting
• High blood pressure
• High blood sugar
• Confusion
• Seizures

What causes lung cancer?

Anyone can get lung cancer, but 90 percent of lung cancer cases are the result of smoking. Smoke damages your lung tissue when  you inhale it. Once lung cells are damaged, they begin to behave abnormally. This increases your risk for lung cancer. Small-cell lung cancer is almost always associated with heavy smoking. When you stop smoking, your lungs may be able to heal, reducing your risk of lung cancer. You can also increase your risk of lung cancer by breathing in hazardous substances such as:

• Radon
• Asbestos
• Arsenic
• Cadmium
• Chromium
• Nickel
• Some petroleum products
• Uranium

Exposure to radon is the second leading cause of lung cancer, according to the American Lung Association. Radon is an odorless, invisible gas naturally released from rocks, soil and water. Research shows that inherited genetic mutations may make you more likely to develop lung cancer, especially if you smoke or are exposed to other carcinogens. Sometimes, there’s no obvious cause for lung cancer.

What are the risk factors for lung cancer?

There are multiple known risk factors for lung cancer. These include:

• Smoking: Smoking is the single biggest risk factor for lung cancer. This includes cigarettes, cigars, and pipes. Tobacco products contain thousands of toxic substances. Cigarette smokers are 15 to 30 times more likely to get lung cancer than nonsmokers.
• Secondhand smoke: Every year in the United States, about 7,300 people who’ve never smoked die from lung cancer caused by secondhand smoke.
• Exposure to radon: Breathing in radon is the leading cause of lung cancer in nonsmokers. It’s a good idea to test your home for levels of radon to reduce your risk.
• Exposure to asbestos, diesel exhaust, and other toxic substances: Breathing in toxic substances can increase your risk, especially if you’re subject to repeat exposure.
• A family history of lung cancer: Having family members with lung cancer increases your risk of lung cancer.
• A personal history of lung cancer: You’re more likely to get lung cancer if you’ve had lung cancer in the past, especially if you’re a smoker.
• Previous radiation therapy to the chest: Radiation therapy can increase your risk of lung cancer.

What is the link between lung cancer and smoking?

Not all smokers get lung cancer, and not everyone who has lung cancer is a smoker. But there’s no doubt that smoking is the biggest risk factor. It’s responsible for 9 out of 10Trusted Source lung cancers. Plus, you don’t have to be a smoker to be affected. Secondhand smoke also increases your risk of lung cancer. In addition to cigarettes, cigar and pipe smoking are also linked to lung cancer.

The more you smoke and the longer you smoke, the greater your chance of developing lung cancer. Former smokers are still at risk of developing lung cancer, but quitting can lower that risk considerably. Within 10 years of quitting smoking, the risk of dying from lung cancer drops by half.

What are the complications of lung cancer?

Lung cancer can lead to complications. These include:

• High risk of infection: People with lung cancer are at an increased risk of pneumonia, bronchitis, and other infections.
• Facial swelling: Tumors in your lungs can restrict blood flow to your upper body and result in facial swelling.
• Loss of lung function: Shortness of breath, difficulty breathing, and other symptoms of reduced lung function can occur in lung cancer patients.
• Blood clots: People with lung cancer are at a higher risk of clots, especially in their lower legs.
• Spitting up blood: Irritation in airways or from tumors can result in spitting up blood.
• Increased calcium in blood: Sometimes, lung cancer can result in hypercalcemia, or increased calcium in your blood.
• Spinal compression: Tumors can press on the spine and cause pain, weakness, and trouble walking.
• Heart blockage: Tumors in your lungs can compress heart vessels and lead to multiple serious heart conditions.
• Nerve pain: Tumors can result in nerve pain along with numbness, tingling, and weakness.
• Trouble swallowing: Lung cancer can spread to your esophagus and cause trouble swallowing.

What are the tips for lung cancer prevention?

There is no guaranteed way to prevent lung cancer. However, you can reduce your risk if you:

• Quit smoking: Smoking is the number-one risk factor for lung cancer. Eliminating smoking greatly reduces your chance of developing lung cancer.
• Avoid radon: You can have your home tested for radon to help reduce your exposure and lung cancer risk.
• Avoid other cancer-causing chemicals: Limiting your exposure to other cancer-causing chemicals can reduce your risk.
• Eat a healthy diet: There is some evidence to suggest that eating a diet high in fruits and vegetables can reduce your risk of lung cancer.

How is lung cancer diagnosed?

Diagnosing lung cancer starts with a conversation with your doctor and a physical exam. They’ll want to go over your health history and any symptoms you’re having. You’ll also need tests to confirm the diagnosis. These might include:

• Imaging tests: An abnormal mass can be seen on X-ray, MRI, CT, and PET scans. These scans produce more detail and find smaller lesions.
• Sputum cytology: If you produce phlegm when you cough, microscopic examination can determine if cancer cells are present.
• Bronchoscopy: While under sedation, a lighted tube is passed down your throat and into your lungs, allowing closer examination of your lung tissue.

You might also have a biopsy. A biopsy is a procedure that involves obtaining a small sample of lung tissue which is then examined under a microscope. A biopsy can determine if tumor cells are cancerous. A biopsy may be performed using one of the following methods:

• Mediastinoscopy: In a mediastinoscopy, your doctor makes an incision at the base of the neck. A lighted instrument is inserted and surgical tools are used to take samples from lymph nodes. It’s usually performed in a hospital under general anesthesia.
• Lung needle biopsy: With this procedure, your doctor inserts a needle through the chest wall and into the suspicious lung tissue. A needle biopsy can also be used to test lymph nodes. It’s usually performed in a hospital and you’ll be given a sedative to help you relax.

If the biopsy results are positive for cancer, you might need additional testing, such as a bone scan, to help determine if cancer has spread and to help with staging.

What are the treatments for lung cancer?

The primary treatments for lung cancer include surgery to remove the tumor, and chemotherapy and radiation treatments to kill cancer cells. Sometimes, newer cancer treatments such as targeted therapy and immunotherapy are also used, but usually not until later stages. As a rule, treatment for non-small cell lung cancer (NSCLC) varies from person to person. Your treatment plan will depend on specific details of your health and on the stage of your cancer when you were diagnosed.